We are studying the cellular and molecular basis of autoimmune diseases with two purposes. First, we want to understand the pathogenic role and antigen-specificity of T cells that cause autoimmune diseases such as multiple sclerosis, clotting factor inhibition, insulin-dependent diabetes, among others. Second, we would like to test specific antigen-induced apoptosis as a means of treating such autoimmune diseases. To these ends, we have made progress in the following areas: 1) we have reinitiated studies of recombinant molecules containing antigens potentially involved in multiple sclerosis with the goal of establishing a Cooperative Research and Development Agreement to test such a form of therapy in a clinical trial. At present there is increasing evidence that myelin proteins antigens are the target of the autoimmune attack. By programmed the T cells that recognize such antigens to die, the effect of eliminating these cells on the disease can be demonstrated. 2) We are studying new highly sensitive diagnostic tests to detect end organ damage during autoimmune diseases to determine if these can provide an early warning system of autoimmune attack;and 3) we are initiating studies of antigen-specific therapy to prevent the formation of blocking antibodies following factor VIII administration to hemophiliacs. These studies will employ new recombinant proteins constructed to contain the principal epitopic regions of Factor VIII to which T cells react. We will also be initiating studies in experimental animals of other autoimmune conditions. In particular, we are focusing on Type I diabetes mellitus and have been studying immune responses against insulin as a harbinger of disease in prediabetic mice and humans. The prediabetic state, known as insulitis, involves both cellular and numeral responses against the islet cells with insulin as the primary antigen. The focused nature of the immune response, which precedes any evident epitope spreading, may allow the use of insulin or congeners thereof as a therapeutic entity. As part of these studies we are trying to understand the molecular regulation of antigen-induced death by T cell receptor stimulation. The deployment of a highly sensitive early warning system as a screening tool to identify individuals with early immune-mediated organ damage with early intervention using antigen-specific treatment approaches, we hope to provide targeted therapy to minimize end-organ damage and clinical disease. to this end, we have prepared extremely sensitive electrochemiluminescence assays that can sensitively and specifically detect FVIII antibodies and insulin autoantibodies. This could better dispose our efforts to intervene early successfully. We believe these investigations will provide important new insights into the pathogenesis of autoimmune diseases and hopefully stimulate the development of new forms of highly specific immune therapy.